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Texium
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A cheap clamp once really put me in danger... I had been melting down some lead to cast an ingot. I had the stainless steel crucible held in a clamp
that I thought was steel. Soon after the lead began to melt, I noticed with horror as the clamp bearing the heavy crucible of molten lead began to
droop. I shut off the burner and frantically rushed to grab my crucible tongs, but it was too late. The clamp snapped off, and I was only narrowly
able to jump out of the way to avoid getting splashed with molten lead. I was picking little bits of lead off the floor and everything else using
tweezers for the rest of that day. It left a bumpy black burn mark on my formica lab bench too. Upon inspection of the broken clamp, I realized that
it was just some crappy pot metal (likely a zinc alloy) plated with nickel.
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Morgan
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I often wish I had some decent clamps for holding hot things. There are these EMT pipe clamps that come in various sizes and they are certainly not
the best/awkward but you can use them if you don't have anything else. By folding some strips of aluminum foil it makes a soft padding for the
glassware so the glass isn't scratched up. I guess some silicone matting material would also do for moderately hot clamp padding. And glass cloth or
high temperature gasket material could be used.
I got an old T-slot pole that was used for a library magazine rack to attach the EMT pipe clamps to but any T-slot will do. I suppose if given enough
thought, you could come up with some sort of nice homemade clamp.
https://www.youtube.com/watch?v=20XcCHnynDY
http://www.pulse-jets.com/phpbb3/download/file.php?id=13716&...
http://www.pulse-jets.com/phpbb3/download/file.php?id=13715&...
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Sulaiman
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If you have the stock and equipment it may be fairly straightforward to fabricate stands and clamps
After two diy attempts I bought new stands and clamps
as the cost is less than buying materials,
if you count transportation / postage.
I bought two types of boss head,
the cheap chrome and blue plastic ones work but give me very little confidence of reliability or safety
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The Volatile Chemist
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Quote: Originally posted by zts16  | | A cheap clamp once really put me in danger... I had been melting down some lead to cast an ingot. I had the stainless steel crucible held in a clamp
that I thought was steel. Soon after the lead began to melt, I noticed with horror as the clamp bearing the heavy crucible of molten lead began to
droop. I shut off the burner and frantically rushed to grab my crucible tongs, but it was too late. The clamp snapped off, and I was only narrowly
able to jump out of the way to avoid getting splashed with molten lead. I was picking little bits of lead off the floor and everything else using
tweezers for the rest of that day. It left a bumpy black burn mark on my formica lab bench too. Upon inspection of the broken clamp, I realized that
it was just some crappy pot metal (likely a zinc alloy) plated with nickel. |
That's terrible. I have a few old, nice, really light ring attachments, but my only clamp is from HST, and really low quality. It's impossible to make
it stay upright, it always tilts to one side. Also, it's held together with a screw at the clamp part, so the clamp itself rotates side-to-side. I
melted the rubber on the clamp, but that of course was my fault.
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Morgan
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Maybe this Turbo Roaster could be repurposed for something. Jam jars are ubiquitous and there're many sizes. And from what I gather it doesn't work as
advertised so maybe you could come up with a better function.
https://www.youtube.com/watch?v=pJgT9VecfWw
http://www.ky3.com/news/local/try-before-you-buy-turbo-roast...
Thumbs down reviews
http://wnep.com/2013/11/28/turbo-roaster/
https://www.youtube.com/watch?v=krd1fsm9KHw
[Edited on 22-1-2016 by Morgan]
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Detonationology
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Confirmed:
Candy thermometers are chemistry friendly! As long as the it is completely encapsulated in glass, it is perfectly compatible with strong acids. And
it has a very high temperature range.
I found mine in the back of a kitchen drawer, but apparently they are also sold at Wal-Mart. Scrape the glass to test ensure it is indeed completely
encapsulated in glass and that the metal on the bottom is not exposed on the outside.
I believe mine had some lead melted into the bottom of the glass in order to give a good place to get temperature readings.
[Edited on 2-4-2016 by Detonationology]
“There are no differences but differences of degree between different degrees of difference and no difference.” ― William James
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The Volatile Chemist
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That's great! I had always wondered about that but never got around to testing the theory they did work well. Many non-scienc-y friends had suggested
them when I complained about low thermometer temperatures. How high does that go?
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Detonationology
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200˚C is the max on mine. I also realized that the diameter of glass is narrow enough to fit snuggly in a 24/40 joint with a generous amount of PTFE
tape.
“There are no differences but differences of degree between different degrees of difference and no difference.” ― William James
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JJay
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I often use candy thermometers for monitoring bath temperatures but have never tried putting them into reagent mixtures.
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The Volatile Chemist
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| Quote: Originally posted by JJay | | I often use candy thermometers for monitoring bath temperatures but have never tried putting them into reagent mixtures. |
Well, that'd be what I'd use mine for. Perhaps also for the top of a still-head or maybe in a reaction vessel making citrazinic acid...
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j_sum1
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Nothing that remarkable here but I thought I'd share anyway.
I just used some packing material and a plastic document holder to make a case for all of my thermometers, glass tubes and pipettes. Less chance of
breaking them ow and they take up less space since I can stack things on top.
Note the candy thermometer. Idea courtesy of this thread. 
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Morgan
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I often use tiny funnels for pouring methanol and happened to notice when trimming the flange of a silicone baby bottle nipple and cutting the tip off
that it would work fine as a funnel for some things. And there're probably a lot of other uses, even though the various shapes and sizes of nipples
might seem an odd thing to adapt for chemistry or lab applications.
Also the silicone wine bottle stoppers that act as a one-way valve with a vacuum saver seal might be of some odd use. The one I have in front of me
has a duckbill valve but there is another design with small holes in a circular pattern.
[Edited on 13-2-2016 by Morgan]
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100PercentChemistry
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Recommend you buy the cd of the golden book of chemistry experiments for 10 bucks. The first chapter is about this. I personally like the close hanger
texture holder
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Detonationology
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My candy thermometer fits very nice and loose at the top of my Liebig condenser for measuring the vapor temp while refluxing. Not much a risk of
pressure build up.
“There are no differences but differences of degree between different degrees of difference and no difference.” ― William James
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Great
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| Quote: Originally posted by Detonationology | | My candy thermometer fits very nice and loose at the top of my Liebig condenser for measuring the vapor temp while refluxing. Not much a risk of
pressure build up. |
The only (mercury) candy thermometers I've seen for sale around here are vintage and not recommended for use. How old is yours?
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j_sum1
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| Quote: Originally posted by 100PercentChemistry | | Recommend you buy the cd of the golden book of chemistry experiments for 10 bucks. The first chapter is about this. I personally like the close hanger
texture holder |
Forget the CD or ten bucks.
Here it is:
http://chemistry.about.com/library/goldenchem.pdf
And in the forum library
http://library.sciencemadness.org/library/books/Brent_GBC.pd...
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Detonationology
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| Quote: Originally posted by Great | | Quote: Originally posted by Detonationology | | My candy thermometer fits very nice and loose at the top of my Liebig condenser for measuring the vapor temp while refluxing. Not much a risk of
pressure build up. |
The only (mercury) candy thermometers I've seen for sale around here are vintage and not recommended for use. How old is yours?
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Mercury? Good God, I couldn't possibly imagine it anywhere near food. Mine has a red liquid, likely alcohol or ethyl acetate, and has to be at least
20 years old.
“There are no differences but differences of degree between different degrees of difference and no difference.” ― William James
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violet sin
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@ great: Pretty sure that is a weighted shot in the bottom, with a standard alcohol thermometer in/on it. I've seen a few that had little lead shot
looking pellets at the tip, with a drop of wax/glue seating them. Guess it's steel shot from some quick reading from disgruntled brewers on Amazon.
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Detonationology
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Yeah, I think it is lead in the bottom. It was likely poured into the pre-heated glass tube, then the actual thermometer part was placed down into
the molten lead to give a good, thermally conductive location to receive temperature readings.
“There are no differences but differences of degree between different degrees of difference and no difference.” ― William James
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The Volatile Chemist
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Are there even mercury thermometers for sale now?
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j_sum1
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I bought one recently.
(It's pretty useless since the graduations are so faint they can't be seen easily. I got a refund.)
Yay!! Free gram of mercury!
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hyfalcon
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Take a black marker and you can temporarily at least re-blacken your graduations.
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nux vomica
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If anyone is interested in a cheap and easy made flask heater I've been trying out a version that uses a 2000 watt heat gun as the heating
source.
It's made out of off cuts from work , the main barrel is 4" s/s tube 3" high, the rest is to suit the gun and mount the support tube ,there is a
perf s/s disc inside the barrel to support the flask when you are setting up and to diffuse the hot air.
I use a triac voltage controller to vary the fan speed and temperature and it will boil 250 mls of water in under 5 minutes
Cheers nux.
 
[Edited on 7-3-2016 by nux vomica]
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NedsHead
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I was unable to find the type of rubber stopper used with wide mouth vacuum flasks (probably because I don't know what they are called) so I cut a
hole in a rubber stopper for furniture legs I found in a hardware store, the fit is nice and tight, I can lift the whole apparatus by the buchner
funnel, not that I will of course.
 
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gerarddekker
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Setting up my own lab. Great ideas here. Thanks all.
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